ELEANOR HALL: The Australian Defence Force has ruled that there was no inappropriate behaviour by Australian troops during a battle in Afghanistan last year, in which one Australian soldier was killed.

The inquiry was hearing allegations that Australian soldiers killed two women and a baby and mistreated others during a search and clearance operation in late November 2007.

However it has found that the soldiers did not breach any rules of engagement.

In Canberra, Samantha Hawley reports.

SAMANTHA HAWLEY: On the night of the 23rd of November, 26-year-old Private Luke Worsley was killed by a single gunshot wound to the head.

The Defence Inquiry has found his death occurred in straightforward circumstances of combat.

KEN GILLESPIE: Private Worsley's actions in identifying a significant threat, informing his teammates and engaging in the threat are assessed as playing a major role in preventing further Australian casualties during the incident.

SAMANTHA HAWLEY: It was a dire day for the Defence Force and a bloody battle after which Australians soldier were accused of killing two women and a baby.

Vice-Chief of the Defence Force Lieutenant General Ken Gillespie says an inquiry into the serious allegations of mistreatment has cleared the Australian soldiers involved of any wrong doing.

KEN GILLESPIE: Three civilians, two females and an infant child, were killed during the operation. It has since been revealed that one of the deceased females were positively identified firing an AK-47 assault rifle at our forces during the engagement and was therefore re-categorised as an enemy combatant.

Defence public released this fact on the 7th of November during a follow up media inquiry into Private Worsley's death.

It's also been determined that the deceased child was in one of the rooms from which two male and one female combatant were engaging Australian forces with AK-47 fire. That said, the death of civilians and non-combatants during any conflict is highly regrettable.

SAMANTHA HAWLEY: Lieutenant General Gillespie says more and more allegations are being made against Australian troops in Afghanistan.

KEN GILLESPIE: We see a growing trend of Taliban activity here of whenever detainees are taken to make allegations that they have mistreated. The net affect of that is that all law abiding nations and particularly the ISF (International Stabilisation Force) countries that you see over there, always take that seriously and always go into an investigation.

And so in some regards, by making these allegations, they're causing us considerable administrative burden. In our case, it's worth going through that burden because our reputation is hard fought.

SAMANTHA HAWLEY: Separate inquiries were also conducted into the deaths of Trooper David Pearce and Sergeant Matthew Locke who were both killed in October last year.

KEN GILLESPIE: Trooper Pearce was killed on the 8th of October 2007 when the Australian light armoured vehicle, or ASLAV he was driving, struck an improvised explosive device which was placed by Taliban extremists.

But the investigating officer found that Trooper Pearce was suitably trained, prepared, and equipped to operate his ASLAV in a high threat environment.

Sergeant Locke was killed on the 25th of October 2007 by a single gunshot wound during a combat engagement with a prepared enemy. Sergeant Locke's combat awareness, leadership and battle-cunning are assessed as playing a major role in preventing further casualties on the day of the incident.

SAMANTHA HAWLEY: An inquiry into the death of Lance Corporal Jason Marks, who was killed in Afghanistan last month, is still underway.